Sofa



FIG. 1 is a top and front perspective view of a sofa showing our new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is an end elevational view thereof, the end view opposite that shown in FIG. 3 being the mirror image thereof; and,

FIG. 4 is rear elevational view thereof. 

The ornamental design for a sofa, as shown and described. 